title: Phosphorylation of protein kinase C-related kinase PRK2 during meiotic maturation of starfish oocytes.
abstract: The resumption of meiosis in the developing starfish oocyte is the result of intracellular signaling events initiated by 1-methyladenine stimulation. One of the earliest detectable kinase activities during meiotic maturation of starfish oocytes is a protein kinase C or PKC-like activity. In this study, several isoforms of protein kinase C were cloned from the oocyte; however, the most abundant PKC-like maternal transcript corresponds to protein kinase C-related kinase 2 (PRK2). PRK2 is expressed in the immature oocyte and at least until germinal vesicle breakdown. Subcellular localization of PRK2 revealed a cytoplasmic distribution in the immature oocyte, which, during meiotic maturation, remained in the cytoplasm but also localized to the disintegrating germinal vesicle. Significantly, PRK2 is phosphorylated in vivo in response to 1-methyladenine which precedes MPF activation, making PRK2 a candidate regulator of early signaling events of meiotic maturation.
authors.affiliation: Department of Zoology, University of Washington, Seattle 98195-1800, USA.
authors.forename: G
authors.initials: G
authors.lastname: Stapleton
authors.forename: C P
authors.initials: CP
authors.lastname: Nguyen
authors.forename: K A
authors.initials: KA
authors.lastname: Lease
authors.forename: M B
authors.initials: MB
authors.lastname: Hille
mesh_terms: D000595:Amino Acid Sequence; D000818:Animals; D001755:Blastocyst / Q000737:chemistry; D016203:CDC2 Protein Kinase / Q000378:metabolism; D003001:Cloning, Molecular; D003593:Cytoplasm / Q000201:enzymology; D019204:GTP-Binding Proteins / Q000032:analysis / Q000235:genetics; D005775:Gastrula / Q000737:chemistry / Q000201:enzymology; D008540:Meiosis / Q000502:physiology*; D008969:Molecular Sequence Data; D009865:Oocytes / Q000737:chemistry / Q000166:cytology / Q000201:enzymology*; D010766:Phosphorylation; D011493:Protein Kinase C / Q000235:genetics / Q000378:metabolism*; D012333:RNA, Messenger / Q000032:analysis; D017422:Sequence Analysis, DNA; D017386:Sequence Homology, Amino Acid; D013215:Starfish / Q000201:enzymology / Q000235:genetics*; D020742:rhoA GTP-Binding Protein
chemical_list: D012333:RNA, Messenger; C061570:protein kinase N; D011493:Protein Kinase C; D016203:CDC2 Protein Kinase; D019204:GTP-Binding Proteins; D020742:rhoA GTP-Binding Protein